264 VAC Line to Line Residential

[kwired]

thats a jump in primary from 7,552 volts to 7,776 volts.

They still have a problem.

If its very intermittent, it could be an arcing regulator switch, or arcing disconnect somewhere on the line.
They need to ride the line out and find the problem, not just try to get out of something..
A good lineman would know primary voltage isn't supposed to fluctuate that much, that quickly.

The mentioned capacitor in the circuit maybe complicated the results some, but there was a problem regardless and likely was one the things you mentioned.

 

[MD Automation]

thats a jump in primary from 7,552 volts to 7,776 volts.

They still have a problem.

Thanks, as always, for taking time to share your knowledge here.

And yes, that 8 volt jump is fairly dramatic. And I saw jumps larger than that in both directions Wed night and yesterday morning. That's the only one I had my phone w/ me to record. I felt bad for all the appliances in the house each time those happened.

I will say my L-L voltage seems much better this morning. At night, it's easy for me to eyeball the lighting changes. During the day, I have to walk downstairs to the panel and watch a Fluke. For this morning at least, it's low 240's and much more "stable" than it was yesterday. Changing by tenths every so often (totally normal). Wednesday night, even w/o the crazy jumps, it was wandering up and down by 3+ volts inside a minute (totally not normal).

I feel I am NOT getting any kid of run around, they acknowledge the problem and it's not on my end clearly. I just hope that after they finish their maintenance upstream of me, things go back to where they were. Crossing fingers.

Problem especially with larger organizations is the preferred number to call for customer service is a call center, and they have limited suggestions for customers to try and from there it is send a work order to the appropriate service shop.

Yeah dealing with these things is often a real hassle because it takes you forever to get to someone who knows anything.

Agreed, my POCO is BGE (Baltimore Gas & Elec) and serves millions of customers. The (mostly) automated phone line is setup to get immediate responses for gas smell or no power. As it should be of course. To their credit, it was not too difficult to reach a real human, but obvs not any kind of technician. She did not really understand what I was talking about (not her fault), she was asking "But your power is on?"

She did say she could take a note from me, create a ticket, and someone would call or come out. And that absolutely happened, though it took 14 hours. The tech yesterday that showed up said it's quite funny sometimes, the info they get on a ticket, for example she might have written a note down for my problem that said...

"Customers states line is too 64"

Have a recording voltmeter? It would be useful to have records to drop on the PoCo if they "don't find anything".

I did have an old Hioki 3 phase power analyzer which would record data in 1 second intervals. You can see it here on top of a small transformer...


But we closed that shop up earlier this year and I'd have to work too hard to track that thing down. Looks your old Dranetz 606 would print a literal tape with data?

And, to their credit, BGE never really came close to the "blame the customer" thing.

I once caught such high voltage at my own place one time because of working on a piece of customer equipment in my shop, I happened to notice high line to line voltage and figured that it had nothing to do with what I was working on.

Feel free to laugh, but for me I was washing my hands in a bathroom sink Wednesday night and thought to myself "Wow, these vanity lights seem crazy bright". Honestly, that's the first thing I noticed. Not long after that I saw the first flicker and that led me downstairs with a DVM to see my service voltage of 264. So those vanity lights were running hot at 132

Anyway - thanks all again for the input and insight. Much appreciated. Hope the story was worth watching!!

 

[zbang]

Yep, the 606 put all the output on a 2"(ish) wide thermal paper tape; the device dates from maybe the 70's. It was almost completely analog with some interesting sample & hold circuits.; I probably still have the manual . (Ought to replace it sometime, but don't want to spend the $$$ for a return of $.)

 

[Jpflex]

So, thinking to post a follow up to this thread, and assuming you have all been munching on popcorn and waiting for the next chapter of “The Customer says his Electricity is Too Good”…

As all suspected, the fault was/is on the POCO side for sure. As best I understand it, it was a stuck (presumably ON) capacitor (PF correction??). Stop reading now if you don’t want any more details.

I opened a ticket last night around 10PM, but nothing happened until a service tech showed up in a bucket truck this morning. He pulled the front of the outdoor meter panel and saw the same ~235 to 255 ish VAC, fluctuating more than he thought it should. After talking to each other for a little bit, and realizing that neither of us were complete nincompoops, he mentioned he wanted to check the output of the secondary (at the bushings) on the 25 kVA pole mounted transformer (replaced in spring 2020). Neither of us thought it would show anything different, but that’s where he thought he might look next (I guess to rule out problems with the underground lateral). But we all know that any problems there are going to cause lower service voltage (L-L), not higher.

Anyway…

He said he was going to try and reach it from my driveway because there was a lot of traffic on my 2 lane rural road.
I said yes, that’s because there is a detour of another road that is funneling more cars past my house than normal.
He laughed and said, yes it’s funny because that detour is some of our other crews working on some lines nearby.

Both of us starting thinking the same thing right away.

I said, “When did they start working on those primary lines”?
He said, “Yesterday”.
Then he said, “When did you first notice this problem”?
I said, “Yesterday”.

So then he jumped back in his truck and started looking up the locations of the nearest regulators or capacitor banks and getting on the phone/radio with the crew that was nearby. I am certain to have some of these details wrong, but from what he explained, while working on some nearby 3 phase lines (my road is fed from the “B” phase of those lines), the crews temporarily re-routed where they were fed from. And so, for the first time yesterday, my 7680 primary was getting sourced from a slightly different “path”. Sorry for the terrible explanation. But from this new source, it was now going thru a PF capacitor bank that my B phase was previously never fed from. Then somebody on his end looked up the cap on that B phase and it reported “ON” when it should not have been. So they sent somebody there to put it in manual and then turn it off (with a hotstick I guess??). He then said that would automatically generate a new ticket for somebody to go look at why that was not operating properly.

Anyway, that's what he tried his best to explain to me. But long story short, it's definitely on their end.

My service voltage is still a bit wonky, meaning up and down. I've not seen numbers like 264 anymore, but low 250s are common, and it dips under 240 as well. And it changes real quick sometimes, and not because any load kicked on or off in the house. That's what I'd like to see stop happening.

Kinda like this...

View attachment 2563139

Just as the mains jump 8 volts in the small gif above, you can see the lighting brighten a bit. I expect this was happening to everybody on this leg, maybe ~ 80 houses.

I will wait a day or 2 till they finish whatever they are doing nearby and hope they restore the original feed to my B phase.

Thanks all, and bonus points for reading all the way down to here

What fluke meter are you using? I have a fluke 88 and oscilloscope from back when I worked automotive but I need something for higher boltage

 

[MD Automation]

What fluke meter are you using? I have a fluke 88 and oscilloscope from back when I worked automotive but I need something for higher boltage

My goto Fluke is a 77III - crazy old at this point. Just refuses to die, and pretty reliable. Doubles as a poor man's tack hammer, plumb bob and wheel chock.

I am not familar with your 88, but I'd be really surprised if it did not measure AC and DC up to 600V. What kind of higher voltage are you looking to measure?

 

[kwired]

Feel free to laugh, but for me I was washing my hands in a bathroom sink Wednesday night and thought to myself "Wow, these vanity lights seem crazy bright". Honestly, that's the first thing I noticed. Not long after that I saw the first flicker and that led me downstairs with a DVM to see my service voltage of 264. So those vanity lights were running hot at 132

The time at my place ended up being some malfunction and tap changer was stuck on highest voltage tap from what I recall.

 

[Hv&Lv]

The time at my place ended up being some malfunction and tap changer was stuck on highest voltage tap from what I recall.

Occasionally we would have that happen on our lines. Especially with the old MJ-XL controls..
I limit the steps now to 5% on each regulator to stop the steps at 8 raise or 8 lower.
Plays hell with our CVR sometimes, but it’s worth it to keep our members from seeing voltages like MD saw..

 

[Jraef]

Glad it had a satisfactory outcome. Often things like this just linger with no resolution until it just goes away mysteriously.

Just for your future reference, ANSI standards for distribution voltage, which means measured at your service terminals, is +-5%. So they were out of spec even at 255. The +-10% is the equipment design tolerance, called the “Utilization Voltage”, but starts with a lower value to account for drop from the service to the load. So a motor design will be 230V +-10% for a 240V +-5% system that might drop 5% by the time it gets to the motor terminals.